.a1{
    margin-left: 60px;
    width: 120px;
    height: 50px;
}
.a2{
    margin-left: 20px;
    width: 120px;
    height: 50px;
}
.a3{
    text-align: right;
    margin-left: 300px;
    width: 70px;
    height: 30px;
}
.a4{
    text-align: right;
    margin-left: 50px;
    width: 70px;
    height: 30px;
}